There are approximately 490,000 bridges over stream and river crossings in the United States with an annual cost estimate of $30 million for scour-related bridge failures. More than 1,000 bridges collapsed in the United States in past 30 years with about 60% of failures caused by excess scour at the supporting foundation systems. Therefore, assessment of scour potential and erosion rate of subsurface profiles supporting these structures is needed during design, operation, and lifetime performance.A new approach for in situ assessment of erosion potential with depth will be the focus of this presentation. The new device is termed “In Situ Erosion Evaluation Probe (ISEEP)” and the process is developed based upon advancing a rod fitted with a truncated cone jet nozzle into the soil. The jet flow velocity and the advancement rate of the probe are used to estimate soil erodibility parameters utilizing the concept of stream power. Results from laboratory testing show the feasibility of the concept, and a proposed approach for the estimation of a critical stream power and a detachment rate coefficient is presented. Numerical modeling and deployment of the device at a North Carolina barrier island site, after the 2011 Hurricane Irene, are used to demonstrate the applicability of the proposed concept. The estimated scour depth based on ISEEP data agreed relatively well with the scour magnitudes computed from the numerical analyses, as ISEEP data reflected the change in the properties of the sand layers with depth. On the other hand, the scour depth computed from empirical equations in literature was unconservative mainly due to the inability to account for the layered subsurface profile. Further validation of the testing procedure and data reduction approach is recommended, including assessing the process applicability for soils with an appreciable percent of fines content.